Avian Conservation Biology and Extinction Drivers

Vocabulary practice flashcards covering avian conservation concepts, extinction drivers, case studies, and conservation frameworks.

Shifting Baseline Syndrome

A gradual change in the accepted norms for the condition of the natural environment due to a lack of past information or lack of experience of past historical conditions.

Conservation Biology

A scientific discipline focused on addressing the loss of biodiversity through the evaluation of human impacts on biodiversity and the development of practical approaches to prevent extinction.

IUCN Red List Categories

A hierarchical conservation assessment framework that categorizes species extinction risk into Extinct (EX), Extinct in the Wild (EW), Globally Threatened [Critically Endangered (CR), Endangered (EN), Vulnerable (VU)], Near Threatened (NT), Least Concern (LC), Data Deficient (DD), and Not Evaluated (NE).

Rarity (Low Density)

An extinction vulnerability factor where individuals require very large spatial ranges and maintain low population densities, making them highly susceptible to environmental changes.

Harpy Eagle (Harpia harpyja)

A large-bodied apex predator classified as Vulnerable by the IUCN, exhibiting a low population density ($0.6 - 1\,\text{individuals}/100\,\text{km}^2$), an extensive range requirement ($15,600,000\,\text{km}^2$), and a slow reproductive rate of typically one chick every 2 years.

Marvelous Spatuletail (Loddigesia mirabilis)

An Endangered hummingbird endemic to Peru, illustrating rarity via small and infrequent patches, with a range of $8,700\,\text{km}^2$, an elevational distribution of $1700\,\text{m} - 3700\,\text{m}$, and an estimated population of only 250 to 999 individuals.

Limited Dispersal Ability

The inability of a species to move across long distances, leading to reduced gene flow, an increased likelihood of inbreeding, heightened resource competition, and diminished population resilience to environmental disturbance.

Kakapo (Strigops habroptila)

A flightless parrot endemic to New Zealand that suffered severe population declines and mainland extirpation due to limited dispersal ability and introduced mammalian predators.

Richard Henry

A conservation pioneer in New Zealand who, using his muzzled dog Lassie, captured and translocated approximately 500 Kakapo from the mainland to Resolution Island between 1896 and 1900 to safeguard them from introduced predators.

Hybridization (Extinction Risk)

The interbreeding between native and invasive or expanding related species, exemplified by the Northern Spotted Owl (Strix occidentalis caurina) hybridizing with and being displaced by the expanding Barred Owl (Strix varia).

Successional Loss of Habitat

The natural transition of an ecosystem's plant and structure community over time that degrades habitat suitability for specialized species unless natural disturbance regimes are maintained.

Kirtland’s Warbler (Setophaga kirtlandii)

A specialized songbird reliant on periodic wildfires to halt ecological succession in young Jack Pine forests, illustrating vulnerability to successional habitat loss.

Escalator to Extinction

A climate change-induced process where warming temperatures force montane species to shift their distributions progressively upslope until they reach the mountaintop and run out of suitable cooler habitat.

European Starling (Sturnus vulgaris)

An invasive bird species introduced to North America in 1890 (100 individuals in Central Park) that multiplied to over 200 million individuals, directly competing with native birds for food and scarce tree cavity nest sites.

Brown Tree Snake (Boiga irregularis)

An invasive reptilian predator introduced to Guam during or after World War II that decimated native biodiversity, causing the extirpation or extinction of most native forest vertebrates.

Guam Kingfisher (Todiramphus cinnamominus)

A forest bird native to Guam that is currently Extinct in the Wild and survives exclusively in captivity following catastrophic predation by the introduced Brown Tree Snake.

Co-extinction

The loss or secondary extinction of a dependent organism resulting directly from the extinction of a mutualist or commensal partner species.

Avian Malaria

A mosquito-borne disease first detected in Hawaii in 1940 that devastated immunologically naïve endemic Hawaiian honeycreepers, forcing surviving populations into high-elevation refugia where temperatures prevent mosquito reproduction.

Passenger Pigeon (Ectopistes migratorius)

A North American bird species with a historic population of 3 to 5 billion individuals that was driven completely extinct in 1914 by massive commercial hunting, collecting, and habitat fragmentation.

Great Auk (Pinguinus impennis)

A large, flightless North Atlantic seabird driven to complete extinction in 1844 on Eldey Island, Iceland, primarily due to intense overharvesting for meat, feathers, and specimen collection.

Dodo (Raphus cucullatus)

A flightless bird endemic to Mauritius that went extinct by 1662 as a result of human overhunting and nest predation by introduced domestic mammals.

Disturbed Habitat

An ecological state characterized by a temporary alteration in environmental conditions that induces a pronounced change in the ecosystem, resulting from natural forces or anthropogenic activities such as plowing, construction, trail use, and clearing.

IUCN Green Status of Species

A standardized conservation metric complementary to the Red List that assesses species recovery potential, conservation dependence, ecological functionality, and viable presence across native geographic ranges.

Biodiversity Hotspot

A biogeographical region with exceptional reservoirs of endemic plant and animal species that is experiencing severe, high-percentage habitat loss and environmental conversion.